Anything FX can do, HBO can do… without Lady Gaga. The Golden Globe-winning “Bad Romance” singer will return to American Horror Story next season, which may center on the Slenderman stabbings. Back in 2014, two 12-year-old girls stabbed another young woman 19 times in the middle of the Waukesha, Wisconsin, woods — they later “claimed they [did it] to show devotion to Slenderman,” a fictional monster created by the Something Awful forums, “to prove he’s real, and so he wouldn’t kill their families.” Both girls have been charged with attempted first-degree intentional homicide.

It’s a fascinating, if horrifying story, and like another monster before him, Slenderman is getting the HBO documentary treatment. In Beware the Slenderman, Irene Taylor Brodsky, whose The Final Inch was nominated for an Oscar, “uses the (fictional) disturbing figure to explore not only the effect that Internet lore has on real-life actions, but also how the digital age is saturating the imagination and actions of children,” according to Indie Wire.

Here’s the official synopsis:

Shot over 18 months with heartbreaking access to the families of the would-be murderers, the film plunges deep down the rabbit hole of their crime, a Boogeyman and our society’s most impressionable consumers of media. The entrance to the internet can quickly lead us to its dark basement, within just a matter of clicks. How much do we hold children responsible for what they find there?

Between this and Making a Murderer, Wisconsin looks more ruthless and messed up than Gotham. Beware the Slenderman premieres at SXSW on March 11, with an HBO airdate TBA. Below, the creepy poster.